The blast occurred at 6:30 pm Thursday night at an industrial park in Sichuan province's Yibin city, according to a statement on the website of the local work safety administration. The injured had been taken to hospital and were in stable condition, county officials said, adding that the resulting fire had been put out.
Photos on a local news site showed what appeared to be the burned out shell of a building surrounded by rubble.
The company that owns the building where the fire occurred is a chemical manufacturer named Hengda, according to the official Xinhua news service. China has been rocked by several industrial accidents in recent years.
A septic tank explosion last November destroyed a wide swathe of a light industrial area in Ningbo, just south of Shanghai.According to local media reports, the three-storey buildings of the factory burnt down to their steel frames and nearby buildings had their windows shattered.It comes amid a drive to strengthen industrial safety, with China ramping up checks over the past year in the wake of some high-profile incidents at coal mines and chemical plants.
The cause of last night's blast at Yibin Hengda Technology in an industrial park several hours south-east of Chengdu, the capital of the south-western province of Sichuan, is not yet known, the local government in Jiang'an county said.
The injured are in a stable condition and an investigation has begun, state news agency Xinhua said.The company, which makes chemicals for the food and pharmaceutical industries, did not immediately answer telephone calls from Reuters.
Photographs on Chinese social media showed a huge fire and plumes of smoke rising from the facility.
The fire, which broke out early yesterday evening, was put out by 11:30pm, the government said in its statement.
A trio of three-storey buildings were reduced to their steel frames by the explosion, the Sichuan Daily newspaper said, citing eyewitness accounts.
Windows of nearby buildings were shattered by the explosion at the factory, which is surrounded by a sand and gravel plant, it added.
The plant has three production lines, making 300 tonnes per year of benzoic acid, which is used in food preservatives, and 2,000 tonnes per year of 5-nitroisophthalic acid, for medicines and dyes, the regional environmental protection bureau says.
China's breakneck pace of economic growth during the past decade has resulted in a spate of industrial accidents.
In 2015, an explosion in a chemical warehouse in the northern port city of Tianjin killed 165 people.
Last year a blast at a petrochemical plant in eastern Shandong province killed eight people and injured nine.
In 2015, giant chemical blasts in a container storage facility killed at least 165 people in the northern port city of Tianjin.
The explosions caused more than $1 billion in damage and sparked widespread anger at a perceived lack of transparency over the accident's causes and its environmental impact.
A government inquiry eventually recommended 123 people be punished. Tianjin's mayor at the time of the accident was sentenced to 12 years in prison for graft in September.
